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Preservation of superior rectal artery in laparoscopically assisted subtotal colectomy with ileorectal anastomosis for slow transit constipation 被引量:8
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作者 Chien-Wei Wu Ta-Wei Pu +5 位作者 Jung-Cheng Kang Cheng-Wen Hsiao Chao-Yang Chen Je-Ming Hu Kuan-Hsun Lin Tzu-Chiao Lin 《World Journal of Gastroenterology》 SCIE CAS 2021年第22期3121-3129,共9页
BACKGROUND Slow transit constipation(STC)has traditionally been considered as a functional disorder.However,evidence is accumulating that suggests that most of the motility alterations in STC might be of a neuropathic... BACKGROUND Slow transit constipation(STC)has traditionally been considered as a functional disorder.However,evidence is accumulating that suggests that most of the motility alterations in STC might be of a neuropathic etiology.If the patient does not meet the diagnosis of pelvic outlet obstruction and poorly response to conservative treatment,surgical intervention with subtotal colectomy may be effective.The most unwanted complication of the procedure is anastomotic leakage,however,preservation of the superior rectal artery(SRA)may reduce its incidence.AIM To evaluate the preservation of the SRA in laparoscopically assisted subtotal colectomy with ileorectal anastomosis in STC patients.METHODS This was a single-center retrospective observational study.STC was diagnosed after a series of examinations which included a colonic transit test,anal manometry,a balloon expulsion test,and a barium enema.Eligible patients underwent laparoscopically assisted total colectomy with ileorectal anastomosis and were examined between January 2016 and January 2018.The operation time,blood loss,time to first flatus,length of hospital days,and incidence of minor or major complications were recorded.RESULTS A total of 32 patients(mean age,42.6 years)who had received laparoscopic assisted subtotal colectomy with ileorectal artery anastomosis and preservation of the SRA.All patients were diagnosed with STC after a series of examinations.The mean operative time was 151 min and the mean blood loss was 119 mL.The mean day of first time to flatus was 3.0 d,and the mean hospital stay was 10.6 d.There were no any patients conversions to laparotomy.Post-operative minor complications including 1 wound infection and 1 case of ileus.There was no surgical mortality.No anastomosis leakage was noted in any of the patients.CONCLUSION Laparoscopically assisted subtotal colectomy with ileorectal anastomosis and preservation of the SRA can significantly improve bowel function with careful patient selection.Sparing the SRA may protect against anastomosis leakage. 展开更多
关键词 slow transit constipation Superior rectal artery anastomosis leakage Laparoscopic-assisted colorectal surgery Iliorectal anastomosis Colonic transit time
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Evidence of Invariance of Time Scale at Critical Point in Ising Meanfield Equilibrium Equation of State
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作者 Muktish Acharyya Ajanta Bhowal Acharyya 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第6期1109-1112,共4页
我们解决 Ising 铁磁物质的状态的平衡 meanfield 方程(从 BraggWilliams 获得了理论) 由 NewtonRaphson 方法。重复的数字要求了得到一个会聚的答案(在指定精确性以内) 在任何特别温度,平衡, magnetisation 被观察尽最大努力分叉温... 我们解决 Ising 铁磁物质的状态的平衡 meanfield 方程(从 BraggWilliams 获得了理论) 由 NewtonRaphson 方法。重复的数字要求了得到一个会聚的答案(在指定精确性以内) 在任何特别温度,平衡, magnetisation 被观察尽最大努力分叉温度接近批评价值的法律时尚。这作为批评慢下来被识别。代表也被估计。代表的这值与从分析答案获得了那相比。除这以外,数字结果也与展出同意的令人满意的度的一些试验性的结果相比。它从这研究被观察在批评的点的时间规模的不变性的信息在 Ising 铁磁物质的状态的 meanfield 平衡方程是在场的。 展开更多
关键词 尺度不变性 平衡方程 临界点 时间 证据 NEWTON 数值模拟 布拉格
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风浪联合作用下OOstar平台低频运动响应分析
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作者 张义哲 顾倩 姜胜超 《中国海洋平台》 2024年第4期1-10,共10页
基于FAST建立OOstar平台的时域模型,研究风浪联合作用下平台的运动响应,采用统计学方法分析平台的不规则运动规律,利用傅里叶变换对平台运动进行频谱分析,重点关注波浪载荷差频分量及风载荷对平台低频慢漂运动的影响。结果表明:在不同... 基于FAST建立OOstar平台的时域模型,研究风浪联合作用下平台的运动响应,采用统计学方法分析平台的不规则运动规律,利用傅里叶变换对平台运动进行频谱分析,重点关注波浪载荷差频分量及风载荷对平台低频慢漂运动的影响。结果表明:在不同海况下差频分量与风载荷均会使平台运动振幅增加,并使大振幅对应运动周期的离散性增强,而对小振幅对应运动周期的影响较小;差频分量对振幅及运动周期的影响随着海况的恶劣而增强,风载荷则相反。频谱分析表明,差频分量在不同海况下对平台自振频率处运动的激励影响均较大,风载荷则在四级海况下对平台自振频率处运动的激励影响较大,在八级海况下对平台自振频率处的激励影响较小。 展开更多
关键词 OOstar平台 风浪联合作用 时域模拟 慢漂运动 频谱分析
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一种适用于双极化火控雷达的慢速目标检测方法及FPGA实现
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作者 汤卫红 《现代导航》 2024年第3期221-225,共5页
针对火控雷达在近区强杂波背景下慢速目标的检测问题,提出了一种适用于双极化火控雷达的慢速目标检测方法。该方法采用脉内分时变极化收发的设计,利用极化正交抑制近区杂波对接收动态的影响,同时,给出基于脉内变初相拉偏目标多普勒的闭... 针对火控雷达在近区强杂波背景下慢速目标的检测问题,提出了一种适用于双极化火控雷达的慢速目标检测方法。该方法采用脉内分时变极化收发的设计,利用极化正交抑制近区杂波对接收动态的影响,同时,给出基于脉内变初相拉偏目标多普勒的闭式解及现场可编程门阵列(FPGA)实现,所提方法能够可靠地实现强杂波背景下慢速目标的检测,工程实现性高。最后,通过仿真验证所提方法的有效性。 展开更多
关键词 杂波 慢速目标检测 变初相 现场可编程门阵列
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Time-Delay Effects on Synchronization of Coupled Slow-Fast Systems
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作者 Yuanguang Zheng Jianjian Zeng 《Journal of Applied Mathematics and Physics》 2021年第4期635-647,共13页
Time-delay effects on synchronization features of delay-coupled slow-fast van der Pol systems are investigated in the present paper. The synchronization mechanism of “slow-manifold adjustment” is firstly described o... Time-delay effects on synchronization features of delay-coupled slow-fast van der Pol systems are investigated in the present paper. The synchronization mechanism of “slow-manifold adjustment” is firstly described on the basis of geometric singular perturbation theory. Then, the impact of time delay on the structure of the slow manifold of synchronized system is obtained by using the method of stability switch, and thus, time-delay effects on synchronization features are stated. It is shown the time delay cannot qualitatively affect the synchronization mechanism, however, it can result in the drift of the optimal coupling strength. 展开更多
关键词 SYNCHRONIZaTION slow-Fast System time-DELaY Geometric Singular Perturbation Theory
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快慢时间域间歇采样转发干扰生成进动锥体ISAR群阵列 被引量:3
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作者 王英 束长勇 +2 位作者 张生俊 黄沛霖 姬金祖 《电子与信息学报》 EI CSCD 北大核心 2016年第2期450-454,共5页
为了提升空间锥体目标突防能力,该文提出一种基于快慢时间域间歇采样转发干扰生成沿距离向及方位向分布的空间锥体ISAR群阵列方法。首先分析了双站情况下空间锥体目标ISAR像成像方法;针对线性调频波分析了快慢时间域间歇采样生成空间锥... 为了提升空间锥体目标突防能力,该文提出一种基于快慢时间域间歇采样转发干扰生成沿距离向及方位向分布的空间锥体ISAR群阵列方法。首先分析了双站情况下空间锥体目标ISAR像成像方法;针对线性调频波分析了快慢时间域间歇采样生成空间锥体ISAR群阵列的基本原理及其ISAR假目标分布特性。最后结合电磁仿真数据,分析了快慢时间域间隙采样参数对ISAR群阵列分布的影响,可为ISAR欺骗式干扰提供参考。 展开更多
关键词 isaR群阵列 间歇采样转发 快慢时间域 进动锥体目标
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基于改进Slow-Only网络的骨骼点动作识别方法研究 被引量:1
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作者 田青 冯赛楠 +3 位作者 魏运 豆飞 赵志强 张超 《工业控制计算机》 2023年第7期54-57,共4页
由于存在人体之间相互遮挡、受环境变化影响较大、时序特征提取能力较弱等问题,现有的动作识别方法在精准度方面仍有不足,因此,提出了一种基于改进Slow-Only网络的骨骼点动作识别方法。首先,将骨骼关键点数据进行预处理,分别在时间和空... 由于存在人体之间相互遮挡、受环境变化影响较大、时序特征提取能力较弱等问题,现有的动作识别方法在精准度方面仍有不足,因此,提出了一种基于改进Slow-Only网络的骨骼点动作识别方法。首先,将骨骼关键点数据进行预处理,分别在时间和空间维度减少冗余信息;其次,基于Slow-Only网络,重新设计了时间卷积模块,以更好地提取视频帧所包含的时序信息;最后,增加了改进的注意力机制模块,以降低遮挡问题带来的影响。在NTU RGB+D数据集上进行了实验,实验结果表明该方法能有效地提升检测精度,并且在实际场景中具有应用价值。 展开更多
关键词 骨骼关键点 slow-Only网络 动作识别 时序特征 通道注意力
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Predicting dynamics of soil organic carbon mineralization with a double exponential model in different forest belts of China 被引量:10
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作者 YANG Li-xia PAN Jian-jun YUAN Shao-feng 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期39-43,共5页
The dynamics of soil organic carbon (SOC) was analyzed by using laboratory incubation and double exponential model that mineralizable SOC was separated into active carbon pools and slow carbon pools in forest soils ... The dynamics of soil organic carbon (SOC) was analyzed by using laboratory incubation and double exponential model that mineralizable SOC was separated into active carbon pools and slow carbon pools in forest soils derived from Changbai and Qilian Mountain areas. By analyzing and fitting the CO2 evolved rates with SOC mineralization, the results showed that active carbon pools accounted tor 1.0% to 8.5% of SOC with an average of mean resistant times (MRTs) for 24 days, and slow carbon pools accounted for 91% to 99% of SOC with an average of MRTs for 179 years. The sizes and MRTs of slow carbon pools showed that SOC in Qilian Mountain sites was more difficult to decompose than that in Changbai Mountain sites. By analyzing the effects of temperature, soil clay content and elevation on SOC mineralization, results indicated that mineralization of SOC was directly related to temperature and that content of accumulated SOC and size of slow carbon pools from Changbai Mountain and Qilian Mountain sites increased linearly with increasing clay content, respectively, which showed temperature and clay content could make greater effect on mineralization of SOC. 展开更多
关键词 Soil organic carbon Organic carbon mineralization Double exponential model active carbon pools slow carbon pools Mean resistant times (MRTs)
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Practical Algorithm for Real-Time Panorama Mosaic
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作者 彭启民 贾云得 柳阳 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期365-368,共4页
A real-time algorithm for cylindrical panorama mosaic from un-calibrated images is presented, A novel scheme based on feature matching is proposed to align the images, Feature candidates are extracted with Plessy's c... A real-time algorithm for cylindrical panorama mosaic from un-calibrated images is presented, A novel scheme based on feature matching is proposed to align the images, Feature candidates are extracted with Plessy's corner detector and then are matehed between eonsecutive frames based on FFT, Overlays between consecutive frames are detected with an improved two-step feature matching. Finally, the images are stitched by fusing in accordance with the found seam linked matched features. This method can be implemented efficiently and show robustness to varying illumination and perspective distortion. 展开更多
关键词 PaNORaMa stitch feature MaTCH OVERLaY real time
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Lower Bounds of Blow Up Time for a Class of Slow Reaction Diffusion Equations with Inner Absorption Terms 被引量:1
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作者 XUE Yingzhen 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2023年第5期373-378,共6页
In this paper,a class of slow reaction-diffusion equations with nonlocal source and inner absorption terms are studied.By using the technique of improved differential inequality,the lower bounds of blow up time for th... In this paper,a class of slow reaction-diffusion equations with nonlocal source and inner absorption terms are studied.By using the technique of improved differential inequality,the lower bounds of blow up time for the system under either homogeneous Dirichlet or nonhomogeneous Neumann boundary conditions are obtained. 展开更多
关键词 slow reaction diffusion equations inner absorption terms lower bounds of blow up time
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Correlation of Surgical Times with Laparoscopic Live Donor Kidney Transplant Outcomes
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作者 Sertac Cimen Sanem Guler +2 位作者 Ian Alwayn Joseph Lawen Bryce Kiberd 《Open Journal of Organ Transplant Surgery》 2013年第4期68-72,共5页
Most studies revealed that ischemic time has substantial role in occurrence of delayed graft function (DGF) after deceased donor kidney transplantation. However, less is known about the potential impact of surgical ti... Most studies revealed that ischemic time has substantial role in occurrence of delayed graft function (DGF) after deceased donor kidney transplantation. However, less is known about the potential impact of surgical times on early outcomes following live donor kidney transplantation. A retrospective cohort of 189 consecutive laparoscopic live donor kidney transplant (LDKT) recipients from January 2006 to August 2012 was analyzed to reveal the impact of pneumoperitoneum time (PT) and anastomosis time (AT) on donor and recipient length of hospital stay and early graft function (EGF). DGF was observed in 13 (6.8%) patients while slow graft function (SGF) was seen in 27 (14%) of the recipients. The median AT was 28 minutes (interquartile range 23, 35 minutes). AT was associated with DGF (Odds Ratio [OR] 1.044, per minute, 95% CI 1.007, 1.082, p = 0.018). Median recipient length of hospital stay was 8 (interquartile range 7, 11) days. Every 13.5 minutes of longer AT was associated with 1 extra day in hospital. The median PT was 180 minutes (interquartile range 144, 234 minutes). PT was associated with both DGF (OR 1.013 per minute, 95% CI 1.005, 1.021, p = 0.001) and SGF (OR 1.009 per minute, 95% CI 1.002, 1.016, p = 0.016). Every extra hour of PT was associated with 0.42 more days in hospital for the donor. Surgical times may be underestimated variables in dictating use of hospital resources. The effect of surgical times on long term hard outcomes entails further study. 展开更多
关键词 Delayed GRaFT FUNCTION slow GRaFT FUNCTION aNaSTOMOSis time PNEUMOPERITONEUM time Kidney Transplantation
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Introducing driving-force information increases the predictability of the North Atlantic Oscillation
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作者 PAN Xinnong WANG Geli YANG Peicai 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第5期329-336,共8页
北大西洋涛动(NAO)是北半球最重要的天气-气候变率模态之一。以往研究大都基于NAO的观测资料和数值模拟结果,分析它的可预报性特征问题。本文首先利用慢特征分析法提取逐日NAO指数的驱动力信息,并将之引入状态空间重构的过程。在此基础... 北大西洋涛动(NAO)是北半球最重要的天气-气候变率模态之一。以往研究大都基于NAO的观测资料和数值模拟结果,分析它的可预报性特征问题。本文首先利用慢特征分析法提取逐日NAO指数的驱动力信息,并将之引入状态空间重构的过程。在此基础上计算引入慢特征信息后的NAO最大Lyapunov指数以及建立NAO的预测模型。结果表明,当引入其慢特征信号以后,NAO指数的可预报性及预报精度可以得到显著提高。并且利用子波分析探测到NAO的驱动力因子与太阳活动、QBO准两年振荡以及年循环相关。 展开更多
关键词 北大西洋涛动 慢特征分析 驱动力特征 时间序列预测
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Extraction method of component waves in full waveform acoustic data and its application
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作者 ZHOU Haoyi MO Xiuwen 《Global Geology》 2020年第1期16-23,共8页
In conventional slowness-time coherence(STC)method,slowness and time need to be searched at the same time,which limits the precision and lowers the efficiency.The dichotomy method combined with slowness-time coherence... In conventional slowness-time coherence(STC)method,slowness and time need to be searched at the same time,which limits the precision and lowers the efficiency.The dichotomy method combined with slowness-time coherence algorithm aims to enhance the efficiency of data processing and to improve the precision.The algorithm changes the searching pattern of conventional slowness-time coherence method to acquire the slowness of component waves in array acoustic logging data.Based on energy ratio of short time window versus long time window and slowness-time coherence method,the algorithm first acquires the arrivals of the component waves using energy ratio of short time window versus long time window method.It then uses the calculated results as the arrivals in conventional slowness-time coherence method,so the slowness-time two-dimensional searching process is simplified to slowness searching process.Based on dichotomy method,the searching pattern is further optimized in replace of the ergodic searching pattern in conventional slowness-time coherence method,which means that as the iteration proceeds,the current searching interval is reduced to half of the former,so the number of searching times is decreased.The dichotomy method combined with slowness-time coherence algorithm is applied to well L in the data processing.Compared with conventional slowness-time coherence method,for compressional wave,the searching efficiency of the algorithm is 4.53 times better,while for Stoneley wave,the searching efficiency is 1.85 times better.Compared with conventional logging data,the average absolute error of the results of the dichotomy method combined with slowness-time coherence algorithm is 1.14μs/ft smaller than that of the conventional method,while the average relative error is 1.2 percent lower.The dichotomy method combined with slowness-time coherence algorithm shows good results in its application,which can enhance the processing efficiency remarkably while getting reliable results at the same time. 展开更多
关键词 array acoustic logging slowness extraction slowness-time coherence method optimized algorithm
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The optimized design of duct net disposal for filter-rods based on topology structure
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作者 Lv wei 《International Journal of Technology Management》 2013年第3期98-100,共3页
关键词 网络拓扑结构 优化设计 过滤棒 出售 管网 柔性制造系统 路由算法 运输时间
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Adaptive Control of Congestion in Tough Wireless Environments Using DCM+ Algorithm
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作者 Rushdi Hamamreh Derar Khader 《International Journal of Communications, Network and System Sciences》 2019年第8期113-123,共11页
The aim of this paper is to present DCM+, a new congestion control protocol for data networks. It stands for Dynamic Congestion control for Mobile networks. New metrics have been newly invented and introduced like nor... The aim of this paper is to present DCM+, a new congestion control protocol for data networks. It stands for Dynamic Congestion control for Mobile networks. New metrics have been newly invented and introduced like normalized advancing index (NAI) and complete transmission time (CTT). The simulations are done for a simple single-hop-topology (sender-router-receiver). The outcomes of this protocol are excellent and, in most cases, better than other approaches. The excellent properties of our proposed protocol were possible through tracking the available slow-start threshold. We achieved performance improvement, minimized end-to-end delay and large reduction in transmission time. DCM+ was able to combine many advantages at same time of the protocols NewReno and Westwood+. The results show, that DCM+ is extremely adequate for different types of networks. Feedback as main principle of control theory was used to control the congestion in the network. The parameters Round-Trip-Time (RTT) and Retransmission Timeout (RTO) are used as feedback signals to adjust the next congestion window (cwnd). 展开更多
关键词 CONGESTION Control Westwood+ slow-Start CONGESTION aVOIDaNCE Bandwidth Estimation Round-Trip time RETRaNSMisSION timeOUT Feedback ns-3
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考虑激励幅值慢变的卷绕头转子系统动力学建模 被引量:1
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作者 王东强 史卫士 +2 位作者 于贺春 董学武 姜海芹 《重庆理工大学学报(自然科学)》 CAS 北大核心 2024年第3期230-239,共10页
卷绕头转子系统结构之间的耦合振动和时频变激励使振动问题十分复杂,为了更准确地研究其动力学特性,根据转子动力学理论,使用有限元方法建立了考虑多盘质量慢变的卷绕头非线性转子系统整机动力学模型,运用Newmark-β数值积分方法对其动... 卷绕头转子系统结构之间的耦合振动和时频变激励使振动问题十分复杂,为了更准确地研究其动力学特性,根据转子动力学理论,使用有限元方法建立了考虑多盘质量慢变的卷绕头非线性转子系统整机动力学模型,运用Newmark-β数值积分方法对其动力学特性求解,得到仅存在初始不平衡量以及卷装不良带来的激励频率、幅值慢变下的非线性动力学行为。通过分析轴心轨迹、时域波形和幅频特性曲线等结果,发现卷绕头转子系统对因卷装不良引起的激励幅值慢变较为敏感,出现新的频率成分。进一步对比分析了不同节点处的振动频谱,其结果可为卷绕头转子系统动力学设计和故障识别提供一定理论支持。 展开更多
关键词 卷绕头转子系统 质量慢变 时频分析 有限元模型 激励幅值慢变 动力学特性
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缓释型抗凝冰剂对SMA-8超薄沥青混合料路用性能影响研究 被引量:1
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作者 徐德根 王小虎 +1 位作者 臧冬冬 刘杰 《北方交通》 2023年第1期30-33,共4页
为了研究缓释型抗凝冰剂析出对SMA-8超薄沥青混合料路用性能的影响规律,通过高温加速浸泡试验,测试不同浸泡时间沥青混合料的路用性能。结果表明:随着浸泡天数的增加,缓释型抗凝冰SMA-8混合料的水稳定性能、抗飞散性能、高温性能、低温... 为了研究缓释型抗凝冰剂析出对SMA-8超薄沥青混合料路用性能的影响规律,通过高温加速浸泡试验,测试不同浸泡时间沥青混合料的路用性能。结果表明:随着浸泡天数的增加,缓释型抗凝冰SMA-8混合料的水稳定性能、抗飞散性能、高温性能、低温性能及疲劳性能都呈一定的下降趋势,但影响程度不同。浸泡12d后混合料仍具有优异的高温性能、低温性能及疲劳性能,但飞散损失率增加2.7倍,浸水残留稳定度和TSR值均已不能满足规范要求,因此,使用时应注意缓释型抗凝冰剂沥青混合料后期的水损害和松散问题。 展开更多
关键词 缓释型抗凝冰剂 SMa-8 超薄铺装 沥青混合料 路用性能 浸泡时间
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“洪氏一针法”在胰十二指肠切除术中的应用
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作者 胡继龙 李其云 +2 位作者 张秉韬 郑志难 孙丽 《沈阳医学院学报》 2024年第2期131-135,共5页
目的:探讨“洪氏一针法”在胰十二指肠切除术(PD)术中应用效果。方法:按照随机数字表法将2021年1月至2022年12月于我院行PD术治疗的40例患者分为2组,各20例。对照组采用胰腺空肠端端套入吻合术,观察组采用“洪氏一针法”行胰肠吻合术。... 目的:探讨“洪氏一针法”在胰十二指肠切除术(PD)术中应用效果。方法:按照随机数字表法将2021年1月至2022年12月于我院行PD术治疗的40例患者分为2组,各20例。对照组采用胰腺空肠端端套入吻合术,观察组采用“洪氏一针法”行胰肠吻合术。比较2组围手术期指标、并发症、二次手术及死亡率、生活质量。结果:观察组胰肠吻合时间、手术时间及住院时间均短于对照组,胰瘘发生率低于对照组,差异有统计学意义(P<0.05);2组术中出血量、胰生化漏、胆瘘、出血、局限性腹腔感染、胃排空障碍、肺部感染发生率及二次手术、死亡率比较,差异均无统计学意义(P>0.05);观察组术后精神健康评分、情感职能评分、社会功能评分、精力评分、一般健康状况评分、躯体疼痛评分、生理职能评分、生理机能评分高于对照组,差异有统计学意义(P<0.05)。结论:PD术中采用“洪氏一针法”行胰肠吻合术有利于缩短胰肠吻合时间、手术时间、住院时间,加快患者术后恢复,减少胰瘘发生率,提高患者生活质量。 展开更多
关键词 胰十二指肠切除术 “洪氏一针法” 胰腺空肠端端套入吻合术 并发症 胰肠吻合时间
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基于慢速时变动力学的空间结构施工过程精细化分析方法研究
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作者 石开荣 陈润洋 姜正荣 《华南地震》 2024年第2期118-127,共10页
针对空间结构施工过程模拟问题,依据时变力学基本原理,提出了基于慢速时变动力学的动态施工过程精细化分析方法。该新方法通过设置与实际施工动态过程相一致的分析时长,引入惯性力和阻尼力,实现时变结构几何、物理及边界等因素间的动态... 针对空间结构施工过程模拟问题,依据时变力学基本原理,提出了基于慢速时变动力学的动态施工过程精细化分析方法。该新方法通过设置与实际施工动态过程相一致的分析时长,引入惯性力和阻尼力,实现时变结构几何、物理及边界等因素间的动态耦联,以达到真正意义上的施工全过程精细化分析。由此给出了该方法的求解思路和实现流程。通过对复杂大跨斜交连廊结构的施工过程分析,并对比施工实测数据,结果表明:该方法的计算值与传统静力施工过程分析方法相吻合,且总体上更接近工程实际,因此可用于空间结构的施工过程分析与安全评估;与传统静力施工过程分析方法相比,该方法一方面能够更准确反映实际施工过程中结构响应的动态累积效应,并获取任意时刻的结构受力和变形情况,另一方面,还可适用于强非线性的复杂施工过程分析(大变形、超大位移、机构位移等),从而避免了传统静力施工过程分析方法中非线性求解的收敛性难题。 展开更多
关键词 空间结构 慢速时变动力学 施工过程 精细化分析
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时间社会学视角下的青年“慢就业” --基于35个个案的质性研究
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作者 魏爽 刘伊 《西部学刊》 2024年第10期36-39,共4页
多数青年毕业后选择顺应社会时钟进入劳动力市场,但也有一部分人将自己的社会时钟“停摆”,成为慢就业青年。对这一群体的心态研究是了解当下青年就业新态势、做好针对性保障工作的前提。通过访谈发现,当下慢就业青年存在低压力、低了... 多数青年毕业后选择顺应社会时钟进入劳动力市场,但也有一部分人将自己的社会时钟“停摆”,成为慢就业青年。对这一群体的心态研究是了解当下青年就业新态势、做好针对性保障工作的前提。通过访谈发现,当下慢就业青年存在低压力、低了解的求职心态;低物欲的生活心态;低社交的交友心态以及高情绪波动的认知心态。 展开更多
关键词 慢就业 时间社会学 青年就业心态
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